The invention relates generally to sensing devices and more particularly to inductor-capacitor-resistor (LCR) sensing devices having enhanced selectivity and sensitivity.
Selectivity of sensors is one of the important aspects in sensor performance and applications. Typically, lack of selectivity prevents the wide use of sensors in sensing chemical and biological species in liquids and air for industrial and other applications. Two known approaches to address the problem associated with lack of selectivity include developing very selective sensing films, and combining individual diverse sensors into an array. Unfortunately, each approach suffers from its own limitations. Highly selective sensing films typically have relatively slow recovery times due to strong vapor-material interactions. Combining sensors into an array may have manufacturing challenges.
Chemical and biological detection has been accomplished using radio frequency identification (RFID) sensors. Sensor response originates from changes in dielectric properties of the sensing film deposited onto a sensor. While RFID sensors can detect individual chemical and physical changes based on changes in dielectric properties, there is a need to further improve selectivity of the RFID sensors.